Aux Battery hide and seek?

mrjlaunch · 09-19-2022, 11:39 AM

Primary 12v Battery:

https://drive.google.com/file/d/1gXK...joTub-6n/view?

Auxiliary Battery:

https://drive.google.com/file/d/19l8...MhILstND/view?

CnSky · 09-19-2022, 01:25 PM

Have a look behind the rear right light cluster easily accessible and see what AH are on that battery.

CnSky · 09-19-2022, 01:29 PM

FYI there is another aux battery in the estate G30 to run the air suspension in the rear axle it's under the hood.

Qsilver7 · 09-20-2022, 09:13 AM

Quote:

Originally Posted by mrjlaunch

I'm officially confused now...
I connected to the car with ISTA+ and it tells me the Auxiliary Battery is 60Ah model not the 90Ah one

I should mention the following for anyone else looking for replacement batteries. They're easily found searching for the BCI (Battery Council International) group as follows:
For the 60Ah battery search online for "type 27 agm battery" example
For the 90Ah battery search online for "type 19 agm battery" example

G6 is your 60 AH auxilliary battery location:

G1 is your 90AH main battery:

CnSky · 09-21-2022, 03:42 PM

I think the manual may be wrong or the names used mixed up.

Reason being is if you disconnect that battery in G6 all Servcies remain working in the vehicle so I think it's the starter battery as it was on all BMW models in the past and the large one under the floor is the Aux which exists to service the gadgets interior lights etc.

I have actually tried this and found it strange the services stay powered.

Maybe it's different in a 530e as I have who knows 🤷*♀️

Qsilver7 · 09-21-2022, 07:22 PM

Maybe the 530e is different…but the main battery does power the cars electrical (which is why it has a larger AH rating). It’s the auxiliary battery that assists with additional power for specific functions like the optional steering, start/stop feature, etc. And the Aux battery usually has a PCU (power control unit) that supports it…which is why it (the aux battery) doesn’t need to be kept on a tender…it has its own “tender”…the PCU.

But again, the 530e may be setup slightly different than the regular ICE vehicles. I think the illustration below is for the 7 series…but the 5/6/8/X5/X6/X7 have similar dual or triple battery setups (some may have an aux battery in the engine bay). But again, the higher AH battery is the main service battery…the smaller AH battery(s) is the aux battery.

shawntech · 03-02-2024, 08:39 PM

Remote software upgrade is failing to begin on my G14 presumably because of voltage (fault 038400 preconditions not met), energy diagnosis test plan passes, my main 105ah battery is 12.95v after charging from underhood recommended oosts however 60ah auxiliary battery is 12.49v which I believe is insufficient. Am I not able to disconnect the cables and charge this battery directly?

09-19-2022, 11:39 AM	#23
mrjlaunch New Member 3 Rep 20 Posts Drives: 2018 530e (G30) Join Date: Dec 2021 Location: England iTrader: (0)	Primary 12v Battery: https://drive.google.com/file/d/1gXK...joTub-6n/view? Auxiliary Battery: https://drive.google.com/file/d/19l8...MhILstND/view?
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09-19-2022, 01:25 PM	#24
CnSky Major 330 Rep 1,028 Posts Drives: BMW 530E 2017 Join Date: Aug 2013 Location: Ireland iTrader: (0)	Have a look behind the rear right light cluster easily accessible and see what AH are on that battery.
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09-19-2022, 01:29 PM	#25
CnSky Major 330 Rep 1,028 Posts Drives: BMW 530E 2017 Join Date: Aug 2013 Location: Ireland iTrader: (0)	FYI there is another aux battery in the estate G30 to run the air suspension in the rear axle it's under the hood.
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09-21-2022, 03:42 PM	#27
CnSky Major 330 Rep 1,028 Posts Drives: BMW 530E 2017 Join Date: Aug 2013 Location: Ireland iTrader: (0)	I think the manual may be wrong or the names used mixed up. Reason being is if you disconnect that battery in G6 all Servcies remain working in the vehicle so I think it's the starter battery as it was on all BMW models in the past and the large one under the floor is the Aux which exists to service the gadgets interior lights etc. I have actually tried this and found it strange the services stay powered. Maybe it's different in a 530e as I have who knows 🤷*♀️
	Appreciate 0 Quote

09-21-2022, 07:22 PM	#28
Qsilver7 Major General 4446 Rep 7,488 Posts Drives: F06 650ix GC / F15 X5 50i Join Date: Oct 2016 Location: Indiana, USA iTrader: (0)	Maybe the 530e is different…but the main battery does power the cars electrical (which is why it has a larger AH rating). It’s the auxiliary battery that assists with additional power for specific functions like the optional steering, start/stop feature, etc. And the Aux battery usually has a PCU (power control unit) that supports it…which is why it (the aux battery) doesn’t need to be kept on a tender…it has its own “tender”…the PCU. But again, the 530e may be setup slightly different than the regular ICE vehicles. I think the illustration below is for the 7 series…but the 5/6/8/X5/X6/X7 have similar dual or triple battery setups (some may have an aux battery in the engine bay). But again, the higher AH battery is the main service battery…the smaller AH battery(s) is the aux battery. Attached Images __________________ 2015 F06 650ix Gran Coupe`(Moonstone/Cohiba Brown)\| 2014 F15 X5 50i MSport (Space Gray/Mocha) Become a BMW CCA member! Click HERE to join and feel free to use my BMW CCA member #191509 as a referral. Last edited by Qsilver7; 09-21-2022 at 07:38 PM..
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03-02-2024, 08:39 PM	#29
shawntech The Wolf 247 Rep 987 Posts Drives: stuff Join Date: Oct 2013 Location: Midwest iTrader: (0) Garage List [0.00] 2019 BMW M850i conv ... [0.00]	Remote software upgrade is failing to begin on my G14 presumably because of voltage (fault 038400 preconditions not met), energy diagnosis test plan passes, my main 105ah battery is 12.95v after charging from underhood recommended oosts however 60ah auxiliary battery is 12.49v which I believe is insufficient. Am I not able to disconnect the cables and charge this battery directly?
	Appreciate 0 Quote